Dereference timers in node.js so that the process may exit when finished

[danthegoodman]

Using the package in a node script is preventing the process from exiting because the reload interval timer has not been marked with unref. This PR resolves that issue.

For testing, I removed the --exit flag that had been previously been forcing mocha to exit immediately even if timers or servers were still open. This also required all servers and timers to in tests to be unrefed as well.

Checklist

• [x] only relevant code is changed (make a diff before you submit the PR)
• [x] run tests npm run test
• [x] tests are included
• [x] commit message and code follows the Developer's Certification of Origin

[danthegoodman]

I didn't update the i18nextHttpBackend.js and ….min.js files because there were more changes in the files than just my targeted changes. I believe this is because the package-lock.json isn't in the repo, which means the babel/browserify packages have probably drifted slightly from the last run.

[adrai]

thank you, it's included in v2.5.2

[danthegoodman]

wow! So quick! Thank you 🎉